1. Global Seismograph Network - GSN: IRIS -2 System

DATES OF OPERATION:  	22 Oct 1993 to Present.

SEISMOMETER TYPE AND ADC:
Streckeisen Model STS-1/VBB 3 component system.  ADC is Quanterra Model Q-680.  
Kinemetrics Model FBA-23 Low-Gain Sensor is used for acceleration channels.

DIGITAL FORMAT:
24 bit integer data words for all components.  Range: +8,388,607 to -8,388,608 counts.

EVENT DETECTOR ALGORITHM:  
The Murdock event detector (Murdock, 1991) is used for the low-gain channels. 

Click on any of the following items for further information.

• Channel Data
• Amplitude Response to Ground Velocity
• Seismic Noise Study graph information
  • Seismic Noise Level - Annual
  • Seismic Noise Level - Seasonal/Diurnal

COMMENTS:
A description of the IRIS-2 system can be found in USGS Open-File Report 89-471, Peterson et al (1989).  
The BCZ calibration channel is programmed manually by the station operator.  It is 
rarely used as the calibration signal interefers with the ultra long-period data.